Non-monotonic composition dependence of the breakdown of Stokes–Einstein relation for water in aqueous solutions of ethanol and 1-propanol: explanation using translational jump-diffusion approach
Shivam Dueby, Vikas Dubey, Sandipa Indra, Snehasis Daschakraborty
Abstract
= 0.2. Diffusion of the water molecules at the maximum SER breakdown point is largely contributed by jump-diffusion. The residual-diffusion, obtained by subtracting the jump-diffusion from the total diffusion, approximately follows the SER for different compositions and temperatures. We also performed hydrogen (H-)bond dynamics and observed that the contribution of jump-diffusion is proportional to the total free energy of activation of breaking all H-bonds that exist around a molecule. This study, therefore, suggests that the more a molecule is trapped by H-bonding, the more likely it is to diffuse through the jump-diffusion mechanism, eventually leading to an increasing degree of SER breakdown.